February, 2024
Data! data! data! […] I can’t make bricks without clay.
― Sherlock Holmes, The Adventure of the Copper Beeches
[R]esearch data represent any material derived from a source of potential information, both measurable and abstract, gathered for analysis or as part of developing findings or insights on a subject.
- Unpublished RDM manuscript.
people, films, photographs, recordings, artifacts, specimens, music score sheets, art, an existing data set…
Scales
Nominal (No Order)
Ordinal (Rank Odering)
Interval (Arbitrary Zero, Quantifiable Difference)
Ratio (Proportional)
Stevens, S. (1946). On the theory of scales of Measurement. Science. 103 (2684).
Collection
Counted (Discrete, Observerd)
Measured (Continuous)
Set (Parameter, Categorical)
Reported (Survey, Nominal, Ordinal, Free Text)
Computational Representations
Numeric (integers, rationals)
Character (strings)
Boolean (true, false)…
Attributes
Dates, Currencies, Coordinates…
The abstraction of data, using shapes, colour, and position.
Data visualization is the graphical display of abstract information for two purposes: sense-making (also called data analysis) and communication.
Stephen Few. Data Visualization for Human Perception.
The greatest value of a picture is when it forces us to notice what we never expected to see.
John W. Tukey (1977). “Exploratory Data Analysis”
[T]he […] optic nerves are sending what we now know are 20 megabits a second of information back to the brain […] [It] is being transformed into information, into thinking, right as that step from the retina to the brain. And the brain is really busy, and it likes to economize. And so it’s quick to be active and jump to conclusions. So if you’re told what to look for, you can’t see anything else.
Edward Tufte. Edward Tufte Wants You to See Better. January 18, 2013. Talk of the Nation. https://www.npr.org/2013/01/18/169708761/edward-tufte-wants-you-to-see-better
There is no data that can be displayed in a pie chart, that cannot be displayed better in some other type of chart.
- John W. Tukey. Attributed quote.
There is no such thing as information overload, just bad design. If something is cluttered and/or confusing, fix your design.
- Edward Tufte. Attributed quote.
A beautiful visualization has a clear goal, a message, or a particular perspective on the information that it is designed to convey. Access to this information should be as straightforward as possible, without sacrificing any necessary, relevant complexity.
Noah Iliinsky (2010). On Beauty. In Beautiful visualization: looking at data through the eyes of experts.
Zewe, A. (June 2, 2022). Making data visualization more accessible for blind and low-vision individuals. MIT News. https://news.mit.edu/2022/data-visualization-accessible-blind-0602
Medium (print, digital, distance)
| Hue | Colour |
| Saturation | Amount of Grey |
| Luminosity | Amount of White and Black |
Try building palettes by adjusting a single element at a time.
| ColorBrewer | Qualitative colour schemes |
| Data Color Picker | Input a colour, request a palette |
| Picular | Word associated colour selections |
| Color Palette Generator | Derive a palette from an image |
| Colour Maps | Generator & Overview |
| Contrast Checker | Evaluate Contrast Ratio |
| Coblis | Colour Blindness Checker |
Activity
Visually represent global greenhouse gas emissions for 2022. Select a plot type (shape and position), colour scale, colour scheme, and discuss labeling and scaling considerations.
Your data set includes the following variables:
| emissions | country | population | gdp | hdi |
|---|---|---|---|---|
| 670 | Canada | 39 | 2140 | 0.936 |
| 266 | Algeria | 45 | 195 | 0.745 |
| 676 | South Korea | 52 | 1670 | 0.925 |
